With vulcanized printing blankets having a smooth surface, it is known to roughen these printing blankets by an abrading process. A surface roughness of 3 to 5 micrometers is obtained by grinding.
The abraded cover layer has good adhesion performance for the paper to be printed because of its roughened surface. The paper comes into contact with the surface of the printing blanket during the printing operation. Paper having different qualities can be excellently processed during printing operations with this abraded printing blanket.
The abrading or grinding process is difficult to carry out since the disadvantage is present that a longitudinal structure is imparted to the cover layer. This longitudinal structure affects the printing quality. Furthermore, producing an abraded printing blanket surface is very time consuming and expensive since several abrading operations are necessary. In addition, the compressibility and softness of the rubber layers in the printing blanket make the method steps difficult to control because the compressibility causes deformation problems over the width. This leads to a thickening of the edges of the cover layer and therefore of the printing blanket.